What are the symptoms of COVID-19?

People who are infected with COVID-19 have developed a wide range of symptoms from mild to severe illness. Symptoms may appear 2-14 days after exposure to the virus and include fever, chills, repeated shaking from chills, cough, shortness of breath or difficulty breathing, eye redness, fatigue, muscle pain, headache, loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, and diarrhea.  Call your health care provider for medical advice if you think you have been exposed to COVID-19 and develop symptoms.

What should I do if I am a close contact to someone with COVID-19 while they were ill, but I am not sick?

You should monitor your health for any symptoms of COVID-19 for 14 days after the last day you were in close contact with the person sick with COVID-19. COVID-19 symptoms may include fever or chills, cough, new loss of sense of smell or taste, fatigue, headache, muscle pain, sore throat, congestion or runny nose, shortness of breath or nausea, vomiting, or diarrhea. You should not go to work or school and should avoid public places for 14 days (unless you are a health care worker or work in critical infrastructure--see below).

Avoid others in your home, including pets. You may be contacted for a public health interview.

If you live with someone who has been diagnosed with COVID-19, review the additional guidance for how to care safely for ill persons:

Caring for Someone Sick at Home (CDC)

Q. Will I have to quarantine if I get my Covid-19 Vaccine?

If you are 2 weeks past your second dose of Moderna or Pfizer OR 2 weeks past your single dose of Johnson & Johnson, you do not have to quarantine if exposed to Covid-19.

What should I do if I had close contact with someone with COVID-19, but I am not sick, and I work in critical infrastructure?

Critical infrastructure includes state and local law enforcement; 911 call center employees; Fusion Center employees; hazardous material responders; janitorial and other custodial staff; and workers in food and agriculture, critical manufacturing, informational technology, transportation, energy and government facilities.

Critical infrastructure workers who had close contact with a COVID-19 case can continue to work as long as they remain well without symptoms and if they take the following measures:

  • Pre-screen. Have temperature and symptom check daily before starting work.
  • Wear a cloth face covering. Use always at work.
  • Social distance. As much as possible, remain at least 6 feet away from coworkers.
  • Disinfect and clean workspaces. Increase frequency of cleaning surfaces and items touched or handled often.
  • Do not share headsets, phones, food, or drinks.

Follow these measures for 14 days after you were last in close contact with a person with COVID-19. Notify your employer and go home immediately if you become sick. Your employer should coordinate with the local health department for guidance.

Additional Information (CDC)

What should I do if I had close contact with someone with COVID-19, but I am not sick, and I am a health care worker?

If possible, you should stay home for 14 days after you were last exposed to this person and monitor for symptoms. If it is not feasible due to staffing needs and if you are asymptomatic, you can return to work. Your workplace must meet specific criteria to determine there is a staffing crisis. If you do work, you should monitor your temperature and for signs of respiratory illness before starting work and for every four hours during your shift. Wear a mask while performing clinical duties for 14 days after your exposure and do not provide patient care to severely immunocompromised patients (e.g., transplant, hematology-oncology).

If you are affiliated with a facility, employee health services will help you to assess your risk and make appropriate recommendations.

Additional information (CDC)

What should I do if I am a close contact to someone with COVID-19 and get sick?

Currently, anyone with COVID-19 symptoms is encouraged to be tested. COVID-19 testing sites can be found on the Illinois Department of Public Health website:

COVID-19 Testing Sites (IDPH)

 If you are over 65 years of age, pregnant, or have medical conditions, you may be at higher risk of COVID-19 complications. Contact your physician’s office and tell them you were exposed to someone with COVID-19. They may want to monitor your health more closely.

If you do not have a higher risk condition but want medical advice, call your health care provider and inform them you were exposed to someone with COVID-19. Your health care provider can help you decide if you need to be evaluated. Testing is recommended for persons with symptoms of COVID-19.

You can contact a free remote health monitoring program for additional guidance or refer to the IDPH and CDC guidance for COVID-19 cases.

Q. What should I do if I lost my Vaccine Card?

Visit VaxVerify provided by IDPH at:

Q. Where can I get the vaccine?

A. If you are an eligible individual as outlined in Phase 1a or 1b (starting February 25), such as health care workers, first responders, essential workers, or anyone 65 years of age and older, you can find your nearest vaccination site:


Q. Will undocumented people be able to get the vaccine?

A. All populations in Illinois, including individuals who are undocumented, can receive the vaccine.  No one will be turned away when it is their time to be vaccinated. 

Q. Do the vaccines require more than one shot?

A. The Johnson & Johnson Janseen vaccine only requires a single dose. The Pfizer-BioNTech and Moderna vaccines require two doses, given weeks apart, to get the most protection.

The first shot of either the Pfizer-BioNTech or Moderna vaccine starts building protection. A second shot a few weeks later is needed to get the most protection the vaccine has to offer. The Pfizer-BioNTech doses should be given 3 weeks (21 days) apart. Moderna doses should be given 1 month (28 days) apart. You should get your second shot as close to the recommended 3-week or 1-month interval as possible. However, there is no maximum interval between the first and second doses for either vaccine. You should not get the second dose earlier than the recommended interval.

With the Johnson & Johnson Janssen vaccine, protection against moderate to severe disease starts about two weeks after being vaccinated.

Q. Which COVID-19 vaccine should I take?

A. Any COVID-19 vaccine authorized by the U.S. Food and Drug Administration (FDA) is expected to be effective. Data available at this point would suggest that the Pfizer-BioNTech and Moderna vaccines are very similar in their abilities to produce immunity to the virus; the Johnson & Johnson Janssen vaccine was nearly 75% effective. The recommendation would be to take whatever vaccine is made available to you. Be sure to receive the booster shot of the Pfizer or Moderna vaccines at the appropriate time. If you choose not to get a second dose, you may reduce the effectiveness of the vaccine. The Johnson & Johnson Janssen vaccine only requires a single dose.

Vaccine Requirements/Mandates

Vaccine Safety

Q. Is a COVID-19 vaccine safe?

A. The U.S. vaccine safety system is a deliberate and multi-phase process to ensure all vaccines are as safe as possible. Safety is a top priority. Vaccine candidates conduct clinical trials with many thousands of study participants to generate scientific data and other information for the FDA to determine their safety and effectiveness.

If the FDA determines a vaccine meets its safety and effectiveness standards, it can make these vaccines available for use in the U.S. by approval or Emergency Use Authorization (EUA). After the FDA makes its determination, ACIP will review the available data in order to make vaccine recommendations to the CDC. ACIP will then recommend vaccine use. After a vaccine is authorized or approved for use, vaccine safety monitoring systems will watch for adverse events (possible side effects). CDC is working to expand safety surveillance through new systems and additional information sources, as well as enhancing existing safety monitoring systems.

Q: How was the COVID-19 vaccine studied?

A: Each authorized COVID-19 vaccine has been studied in large trials of over 30,000 volunteers and shown to be highly effective in preventing COVID-19 disease. The trials involved people of different ages, sex, race/ethnicity, weight, and medical conditions.

Pregnant women and people with weakened immune systems were excluded from the COVID-19 vaccine trials, and so the currently available studies do not provide direct information about vaccine safety and effectiveness in these groups of people. The CDC recommends that those who are pregnant consult with their doctor before taking the vaccine.

Q. Can the COVID-19 vaccine cause me to become infected or infect others?

A. No, you cannot become infected or infect others from receiving the COVID-19 vaccine, because the vaccine contains no live virus. Instead, the vaccine directs your body to produce a protein that teaches your body how to fight off the virus.

Q. How long will it take for COVID-19 vaccines to take effect?

A. The Pfizer-BioNTech and Moderna COVID-19 vaccines are expected to provide some protection a couple of weeks after your first shot and reaches its greatest effectiveness after your second shot. It is very important to take the second shot within the recommended time period for maximum vaccine effectiveness. The Johnson & Johnson Janssen vaccine is effective 14 days after vaccination.

Q. Can I get a COVID-19 vaccine if I am pregnant?

A. COVID-19 vaccines should be administered to pregnant individuals who choose to be vaccinated. Pregnant individuals can receive a COVID-19 vaccine in any setting authorized to administer these vaccines, including any clinical setting and nonclinical community-based vaccination sites, such as schools, community centers, and other mass vaccination locations. If you have questions about getting vaccinated, talking with a health care provider may help you make an informed decision. While a conversation with a health care provider may be helpful, it is not required prior to vaccination.

Q. Can the COVID-19 vaccine make me sick with COVID-19?

A. No. The COVID-19 vaccines do not contain the live virus that causes COVID-19. This means that a COVID-19 vaccine cannot make you sick. The vaccine teaches our immune systems how to recognize and fight the virus that causes COVID-19. Sometimes this process can cause symptoms, such as fever. These symptoms are normal and are a sign that the body is building protection against the virus that causes COVID-19.

Q. After getting a flu shot, I always get the flu. Will this cause me to get COVID-19?

A. No, you cannot become infected, or infect others, from receiving the COVID-19 vaccine, because the vaccine contains no live virus. Instead, the vaccine directs your body to produce a protein that teaches your body how to fight off the virus. Some people develop flu-like symptoms, such as mild fever and muscle aches, after getting a flu vaccination. These symptoms are not the same as having influenza.

Q. I have allergies. Is this vaccine safe for me?

A. While serious allergic reactions were not seen in vaccine clinical trials of thousands of patients, rare allergic reactions to vaccines are possible. If you have a history of serious allergic reactions, you should discuss your situation with your healthcare provider. The COVID-19 vaccine does not contain any animal products such as eggs.

Q. What are the side effects of this vaccine?

A. Some people may experience side effects, which are a part of the normal immune response to a vaccine. The majority of the side effects, while not seen in every individual, are signs that your body is recognizing the vaccine and mounting an immune response. Based on prior studies, side effects may include pain, redness and swelling at the site of the injection., fatigue, headache, muscle pain, chills, joint pain, fever, nausea, malaise, and swollen lymph nodes. These symptoms may occur within 2 days after the shot and last 1 to 2 days. Side effects may be more frequent after the 2nd shot (booster) and less frequent among older adults

Long-term side effects are unknown, although most vaccines do not have long-term side effects. Vaccine studies are ongoing and will continue to monitor and watch for adverse events.

Q. How long will the vaccine protect me from COVID-19? Will this be an annual vaccination, like the flu?

A. We are still learning about length of immunity. To determine how long protection lasts, follow-up studies are required to detect levels of both types of immune responses – antibody and T cell – as well as any repeated exposure risks. As more information becomes available, more information will be shared on the length of immunity.

Q. Can I get COVID-19 after the first dose of the vaccine?

A. Although the first dose of the Pfizer-BioNTech or Moderna vaccine offers some immunity, you will still be considered susceptible to COVID-19. The first dose of the vaccine will provide some protection, but the recommendation is to receive two doses to be protected as intended. Pfizer-BioNTech and Moderna have indicated that after the two doses their vaccines are approximately 95% effective.

The Johnson & Johnson Janssen vaccine only requires a single dose and is more than 74% effective after 14 days.

Q. Is this vaccine preservative free?

A. Yes. The vaccines currently offered are preservative free.


Q. Will a COVID-19 vaccination protect me from getting sick with COVID-19?

A. Yes. COVID-19 vaccination works by teaching your immune system how to recognize and fight the virus that causes COVID-19, and this protects you from getting sick with COVID-19.

The first two vaccines approved for use in the U.S. – one by Pfizer-BioNTech, the other by Moderna – are known as mRNA vaccines and contain material from the COVID-19 virus that gives our cells instructions to make a harmless protein that is unique to the virus. After our cells make copies of the protein, they destroy the genetic material from the vaccine. Our bodies recognize that the protein should not be there and build T-lymphocytes and B-lymphocytes that will remember how to fight the COVID-19 virus if we are infected in the future.

The Johnson & Johnson Janssen vaccine employs a common cold virus genetically engineered to infect cells and deliver genetic instructions to stimulate an overwhelming immune response. The vaccine uses the cold virus (called adenovirus type 26) to deliver a piece of genetic material (DNA) to make the distinctive “spike” protein found on the surface of the COVID-19 virus. The altered cold virus enters cells and follows the genetic instructions to replicate the coronavirus spike. The body’s immune system can then use these replicas to recognize and to react defensively, triggering an immune response against the actual COVID-19 virus.

Q. How many people need to get vaccinated to have herd immunity to COVID-19?

A. The percentage of people who need to have protection in order to achieve herd immunity varies by disease. Scientists estimate that to control COVID-19 and reach herd immunity, about 7 or 8 of every 10 people (75%-80%) will need to be immune.

Q. If I get the vaccine, can I quit wearing a mask?

A. No. While the COVID-19 vaccine is highly effective, it is not 100% effective. Until the COVID-19 pandemic is controlled, people who receive the vaccine need to continue following Illinois Department of Public Health guidance, such as the use of face masks, social distancing, regular hand washing, and avoiding crowds and poorly ventilated spaces. Even after vaccination you can be an asymptomatic carrier of the COVID-19 virus and possibly infect others.

Q: Can I get more than one vaccine?

A: No. Current CDC guidance states that the Pfizer-BioNTech and Moderna vaccines are not interchangeable. You should not get more than one type of coronavirus vaccine, and you should not mix the two-dose vaccines.

Q: Is it possible to compare the effectiveness of the three COVID-19 vaccines?

A: No. The only way to accurately compare the effectiveness of vaccines is by direct comparison in head-to-head clinical trials, which did not occur for these vaccines. Furthermore, the clinical trials for these vaccines occurred in different geographic regions and at different points in time with varying incidence of COVID-19.

Q: When will masking and social distancing be able to end, allowing us to get back to normal life?

A: Given the time it takes to get large quantities of the vaccine produced and distributed, we will need to continue our current mitigation practices for some time. It will remain important that vaccinated people continue to wear masks, practice social distancing and good hand hygiene to help prevent spread. Community infection rates will be continuously monitored and will be used to guide the decision process.

Q. How much will this vaccine cost me? Is it covered by my insurance?

A. There is no cost for the vaccine. However, vaccination providers can charge an administration fee for giving the shot that is reimbursed by the patient’s public or private insurance company or, for uninsured patients, by the Health Resources and Services Administration at the U.S. Department of Health and Human Services. No one can be denied a vaccine if they are unable to pay a vaccine administration fee.